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The effect of two types of scanning strategies on the grain structure and build-up of Residual Stress (RS) has been investigated in an as-built IN718 alloy produced by Laser Powder Bed Fusion (LPBF). The RS state has been investigated by X-ray diffraction techniques. The microstructural characterization was performed principally by Electron Backscatter Diffraction (EBSD), where the application of a post-measurement refinement technique enables small misorientations (< 2°) to be resolved. Kernel average misorientation (KAM) distributions indicate that preferably oriented columnar grains contain higher levels of misorientation, when compared to elongated grains with lower texture. The KAM distributions combined with X-ray diffraction stress maps infer that the increased misorientation is induced via plastic deformation driven by the thermal stresses, acting to self-relieve stress. The possibility of obtaining lower RS states in the build direction as a consequence of the influence of the microstructure should be considered when envisaging scanning strategies aimed at the mitigation of RS.
Pre-Inca civilizations like the coastal cultures Moche and Nazca (Early Intermediate) and the inland culture Wari (Middle Horizon) were agrarian societies which supported indigenous elites of impressive wealth, power, and organization. With the expansion of the Wari Empire, the polychrome style and technique of Nazca propagated to the other cultures. High status burials, most of the Late Moche Fine Line ceramics and a large corpus of ceramics with Wari-derived decoration have been recovered in San José de Moro since 1991. The degree of transfer of procedures in this highly interactive scenario is of special interest: is there a limitation to decoration or is it adopted by the local potters also regarding the formulation of the ceramic bodies? In this context the relative amount, size and type of incorporated non-plastic inclusions as temper are important.